In the case where a medication does not have suitable anti-microbial activity, an injectable formulation containing the medication should be provided with an anti-microbial preservative or any suitable additive, to prevent proliferation or contamination of microorganisms.
Specifically, a multiple-dose injection may be a formulation wherein the injection is drawn (or extracted) several times from a vial or, otherwise, an injection needle is stuck in a cartridge several times, thus being used. In order to prepare against contamination of the microorganisms possibly occurring while repeatedly using, high antimicrobial activity is needed.
Although numerous studies and investigations into aqueous injectable formulations having improved preservative abilities have been implemented, a non-aqueous injectable formulation with high preservative ability has yet to be disclosed.